diff options
Diffstat (limited to 'src/libstore/worker-protocol.hh')
| -rw-r--r-- | src/libstore/worker-protocol.hh | 186 |
1 files changed, 118 insertions, 68 deletions
diff --git a/src/libstore/worker-protocol.hh b/src/libstore/worker-protocol.hh index 18a4e11b2..cd6801290 100644 --- a/src/libstore/worker-protocol.hh +++ b/src/libstore/worker-protocol.hh @@ -14,57 +14,6 @@ namespace nix { #define GET_PROTOCOL_MINOR(x) ((x) & 0x00ff) -/** - * Enumeration of all the request types for the "worker protocol", used - * by unix:// and ssh-ng:// stores. - */ -typedef enum { - wopIsValidPath = 1, - wopHasSubstitutes = 3, - wopQueryPathHash = 4, // obsolete - wopQueryReferences = 5, // obsolete - wopQueryReferrers = 6, - wopAddToStore = 7, - wopAddTextToStore = 8, // obsolete since 1.25, Nix 3.0. Use wopAddToStore - wopBuildPaths = 9, - wopEnsurePath = 10, - wopAddTempRoot = 11, - wopAddIndirectRoot = 12, - wopSyncWithGC = 13, - wopFindRoots = 14, - wopExportPath = 16, // obsolete - wopQueryDeriver = 18, // obsolete - wopSetOptions = 19, - wopCollectGarbage = 20, - wopQuerySubstitutablePathInfo = 21, - wopQueryDerivationOutputs = 22, // obsolete - wopQueryAllValidPaths = 23, - wopQueryFailedPaths = 24, - wopClearFailedPaths = 25, - wopQueryPathInfo = 26, - wopImportPaths = 27, // obsolete - wopQueryDerivationOutputNames = 28, // obsolete - wopQueryPathFromHashPart = 29, - wopQuerySubstitutablePathInfos = 30, - wopQueryValidPaths = 31, - wopQuerySubstitutablePaths = 32, - wopQueryValidDerivers = 33, - wopOptimiseStore = 34, - wopVerifyStore = 35, - wopBuildDerivation = 36, - wopAddSignatures = 37, - wopNarFromPath = 38, - wopAddToStoreNar = 39, - wopQueryMissing = 40, - wopQueryDerivationOutputMap = 41, - wopRegisterDrvOutput = 42, - wopQueryRealisation = 43, - wopAddMultipleToStore = 44, - wopAddBuildLog = 45, - wopBuildPathsWithResults = 46, -} WorkerOp; - - #define STDERR_NEXT 0x6f6c6d67 #define STDERR_READ 0x64617461 // data needed from source #define STDERR_WRITE 0x64617416 // data for sink @@ -78,7 +27,7 @@ typedef enum { class Store; struct Source; -// items being serialized +// items being serialised struct DerivedPath; struct DrvOutput; struct Realisation; @@ -88,31 +37,132 @@ enum TrustedFlag : bool; /** - * Data type for canonical pairs of serializers for the worker protocol. + * The "worker protocol", used by unix:// and ssh-ng:// stores. * - * See https://en.cppreference.com/w/cpp/language/adl for the broader - * concept of what is going on here. + * This `struct` is basically just a `namespace`; We use a type rather + * than a namespace just so we can use it as a template argument. */ -template<typename T> -struct WorkerProto { - static T read(const Store & store, Source & from); - static void write(const Store & store, Sink & out, const T & t); +struct WorkerProto +{ + /** + * Enumeration of all the request types for the protocol. + */ + enum struct Op : uint64_t; + + /** + * Data type for canonical pairs of serialisers for the worker protocol. + * + * See https://en.cppreference.com/w/cpp/language/adl for the broader + * concept of what is going on here. + */ + template<typename T> + struct Serialise; + // This is the definition of `Serialise` we *want* to put here, but + // do not do so. + // + // The problem is that if we do so, C++ will think we have + // seralisers for *all* types. We don't, of course, but that won't + // cause an error until link time. That makes for long debug cycles + // when there is a missing serialiser. + // + // By not defining it globally, and instead letting individual + // serialisers specialise the type, we get back the compile-time + // errors we would like. When no serialiser exists, C++ sees an + // abstract "incomplete" type with no definition, and any attempt to + // use `to` or `from` static methods is a compile-time error because + // they don't exist on an incomplete type. + // + // This makes for a quicker debug cycle, as desired. +#if 0 + { + static T read(const Store & store, Source & from); + static void write(const Store & store, Sink & out, const T & t); + }; +#endif + + /** + * Wrapper function around `WorkerProto::Serialise<T>::write` that allows us to + * infer the type instead of having to write it down explicitly. + */ + template<typename T> + static void write(const Store & store, Sink & out, const T & t) + { + WorkerProto::Serialise<T>::write(store, out, t); + } +}; + +enum struct WorkerProto::Op : uint64_t +{ + IsValidPath = 1, + HasSubstitutes = 3, + QueryPathHash = 4, // obsolete + QueryReferences = 5, // obsolete + QueryReferrers = 6, + AddToStore = 7, + AddTextToStore = 8, // obsolete since 1.25, Nix 3.0. Use WorkerProto::Op::AddToStore + BuildPaths = 9, + EnsurePath = 10, + AddTempRoot = 11, + AddIndirectRoot = 12, + SyncWithGC = 13, + FindRoots = 14, + ExportPath = 16, // obsolete + QueryDeriver = 18, // obsolete + SetOptions = 19, + CollectGarbage = 20, + QuerySubstitutablePathInfo = 21, + QueryDerivationOutputs = 22, // obsolete + QueryAllValidPaths = 23, + QueryFailedPaths = 24, + ClearFailedPaths = 25, + QueryPathInfo = 26, + ImportPaths = 27, // obsolete + QueryDerivationOutputNames = 28, // obsolete + QueryPathFromHashPart = 29, + QuerySubstitutablePathInfos = 30, + QueryValidPaths = 31, + QuerySubstitutablePaths = 32, + QueryValidDerivers = 33, + OptimiseStore = 34, + VerifyStore = 35, + BuildDerivation = 36, + AddSignatures = 37, + NarFromPath = 38, + AddToStoreNar = 39, + QueryMissing = 40, + QueryDerivationOutputMap = 41, + RegisterDrvOutput = 42, + QueryRealisation = 43, + AddMultipleToStore = 44, + AddBuildLog = 45, + BuildPathsWithResults = 46, }; /** - * Wrapper function around `WorkerProto<T>::write` that allows us to - * infer the type instead of having to write it down explicitly. + * Convenience for sending operation codes. + * + * @todo Switch to using `WorkerProto::Serialise` instead probably. But + * this was not done at this time so there would be less churn. */ -template<typename T> -void workerProtoWrite(const Store & store, Sink & out, const T & t) +inline Sink & operator << (Sink & sink, WorkerProto::Op op) +{ + return sink << (uint64_t) op; +} + +/** + * Convenience for debugging. + * + * @todo Perhaps render known opcodes more nicely. + */ +inline std::ostream & operator << (std::ostream & s, WorkerProto::Op op) { - WorkerProto<T>::write(store, out, t); + return s << (uint64_t) op; } /** - * Declare a canonical serializer pair for the worker protocol. + * Declare a canonical serialiser pair for the worker protocol. * - * We specialize the struct merely to indicate that we are implementing + * We specialise the struct merely to indicate that we are implementing * the function for the given type. * * Some sort of `template<...>` must be used with the caller for this to @@ -120,7 +170,7 @@ void workerProtoWrite(const Store & store, Sink & out, const T & t) * practice. */ #define MAKE_WORKER_PROTO(T) \ - struct WorkerProto< T > { \ + struct WorkerProto::Serialise< T > { \ static T read(const Store & store, Source & from); \ static void write(const Store & store, Sink & out, const T & t); \ }; @@ -156,7 +206,7 @@ MAKE_WORKER_PROTO(X_); /** * These use the empty string for the null case, relying on the fact - * that the underlying types never serialize to the empty string. + * that the underlying types never serialise to the empty string. * * We do this instead of a generic std::optional<T> instance because * ordinal tags (0 or 1, here) are a bit of a compatability hazard. 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